Index

The term cloning is used by scientists to describe many different processes that involve making duplicates of biological material. In most cases, isolated genes or cells are duplicated which is used to produce an embryo from which cells called embryonic stem (ES) cells.

Advertisement

The cloning debate was reopened with a new twist late in 1998, when two scientific reports were published regarding the successful isolation of human stem cells. Stem cells are unique and essential cells found in animals that are capable of continually reproducing themselves and renewing tissue throughout an individual organism's life.

Stem cell research is being pursued in the hope of achieving major medical breakthroughs. Scientists are striving to create therapies that rebuild or replace damaged cells with tissues grown from stem cells and offer hope to people suffering from cancer, diabetes, cardiovascular disease, spinal-cord injuries, and many other disorders. Both adult and embryonic stem cells may also provide a route for scientists to develop valuable new methods of drug discovery and testing. They are also powerful tools for doing the research that leads to a better understanding of the basic biology of the human body.

For those who believe that the embryo has the moral status of a person from the moment of conception, research or any other activity that would destroy it is wrong. Human embryos are not mere biological tissues or clusters of cells; they are the tiniest of human beings.33 Thus, we have a moral responsibility not to deliberately harm them.

The potential of stem cell research to understand and treat disease has been demonstrated in animals since 2001. In the case of juvenile diabetes, the promise remains significant, especially in efforts to coax stem cells to become insulin-producing beta cells that could be transplanted into patients.

But research progress in the U.S. with human embryonic stem cells has been disappointing, at best. The development of a robust research community focused on embryonic stem cell investigation has been slowed by political issues, ethical debate, funding considerations, intellectual property concerns, and difficulty in recruiting scientists to the field.

In a January 2004 report, the President's Council on Bioethics says a challenge to the ethical debate about embryonic stem cell research is that so much is unknown. No human therapies have been developed, even though scientists are excited about the potential of the research to save human lives. Some are concerned about the potential misapplication of the technique for reproductive cloning purposes. Other ethical considerations include egg donation, which requires informed consent, and the possible destruction of blastocysts.

Some of the major ethical questions involved with embryonic stem cell research are:

Is it acceptable to destroy a human embryo for research if it will someday result in lifesaving therapies?

Under what circumstances can embryos be ethically donated for research?

Is it right to use somatic cell nuclear transfer, or SCNT, to produce embryos for research?

How does the language used sway public opinion?

Existing ban prohibits the use "“research in which a human embryo or embryos are destroyed, discarded, or knowingly subjected to risk of injury or death....” Current law against funding research in which human embryos are harmed and destroyed reflects well-established national and international legal and ethical norms against the misuse of any human being for research purposes.

Few months back, scientists in the north-east of England were granted permission to offer cheap IVF treatment to women willing to donate eggs for therapeutic cloning and stem cell research. The eggs were to be used to create cloned embryos from which stem cells could be extracted. The decision was attacked by groups opposed to embryo research, and some scientists, for in effect inviting women to "sell" their eggs.

In a bid to sidestep the ethical debate over the use of human embryos in medical research, scientists have developed a way to derive viable stem cell lines without harming the embryo.

They did so by extracting a single cell from the embryo -- as in vitro fertilization clinics do when they test for genetic defects -- and introducing a common molecule called laminin to keep it in a stem cell, or pluripotent, state. Subsequent development of the embryo was unaffected by the biopsy, according to the study published Thursday by the journal Cell Stem Cell.

The new technique holds the promise of dramatically speeding up clinical applications of stem cell therapies for a wide range of debilitating diseases and illnesses. Stem cells are considered a potential magic bullet because they can be transformed into any cell in the body and potentially used to help replace damaged or diseased cells, tissues and organs.

However, embryonic stem cell research is highly controversial because, until now, viable embryos were destroyed in the process of extracting the stem cells. Two groups of scientists recently bypassed this problem by transforming human skin cells into stem cells.

Skin cells will likely become the most common source of stem cells, said Australian researcher Alan Trounson, who heads the world's biggest stem cell research project at the California Institute for Regenerative Medicine. But skin cells are still far from ready for clinical use because the transformation process introduces potentially deadly genetic alterations and viruses.

Which means embryonic stem cells, which do not carry the same risk of mutation, are currently the only option for therapeutic applications, Trounson said. "There will (also) be a lot of people interested in the embryonic stem cells because they are the gold standard," he told AFP, explaining that the stem cells derived from skin have not been fully investigated.

Stem cell pioneer Robert Lanza hopes the technique he helped develop to preserve the embryo will spur US regulators to allow funding for research on new embryonic stem cell lines. Progress in the promising field has been stifled by restrictions on access to federal funds in the United States and outright bans on embryonic research in other countries due to ethical concerns.

"Within the next few months we could make as many of these cells as we like," said Lanza, chief scientific officer at Advanced Cell Technology.

However, the research has raised concerns among scientists and lobby groups.Some are:

Lanza also cautioned against relying upon the stem cells derived from skin. "I've been in this field for too long and been fooled too many times. When you have something you move ahead," Lanza said in a telephone interview.

"We still don't know the dangers of taking a biopsy from an early stage embryo, whether it has any effect on the baby's future development. On paper it looks like an ethical solution, but that requires the biopsy to be completely harmless."-By: Josephine Quintavalle, of Comment on Reproductive Ethics.

"It requires couples having IVF to give permission to have cells taken from their embryos and it's extremely unlikely a couple would want to do that,"-By: a stem cell expert at the National Institute for Medical Research in London.

"It would be very unfortunate if this became seen as the only route to derive human embryonic stem cells. We still need more and we need more research on how to derive them,"- By: Ian Wilmut, at Edinburgh University.